This invention generally relates to a telephone adapted for dialing by touch. More specifically, this invention relates to a telephone having a key pad in which certain keys have been modified to facilitate the dialing of emergency calls by touch.
In almost all parts of the United States of America, emergency services can be summoned by dialing “911” from any telephone. In many areas, so-called “enhanced 911” systems are deployed. In such systems, the emergency operator, on receiving a 911 call from a telephone in a fixed location, is immediately advised of the address from which the call is being made, so that emergency personnel can be dispatched to the proper location even if the person making the call is unable to speak to the operator.
It may thus be a matter of life and death for a person in an emergency situation to be able to dial 911 without delay. However, it is obvious that many emergency situations make dialing a telephone difficult. A person alone and taken ill during the night may be able to find a telephone but may have difficulty locating his or her spectacles or contact lenses. In some emergencies, especially fires, electric power may be cut off, resulting in no or inadequate lighting for a user to see keys on a telephone, or a room may become filled with smoke, with similar results. Under such difficult conditions, a panicked or fearful person can easily pick up the handset of a cordless telephone, or a cellular telephone, upside down, and press the wrong keys, thus either failing to dial any number whatsoever, or a number which will not connect to the emergency operator.
To avoid these problems, it is desirable that telephones provide some way in which 911 can be dialed by touch, without the need for the user to see the key pad. Attempts have, of course, long been made to modify telephones to enable them to be used by the blind or visually impaired; see, for example, U.S. Pat. Nos. 2,754,370 and 4,119,809, both of which describe methods for modifying the dials of rotary dial telephones so as to place the Braille equivalents of the digits 0 and 1 to 9 adjacent to the relevant finger holes in the dial, so enabling the telephone to be dialed by a blind person. Obviously, a telephone with a key pad could be modified in the same manner by placing the Braille equivalents of the digits on or adjacent the relevant keys. However, such a Braille-modified key pad is emphatically not what a typical sighted user needs in an emergency situation. Braille is only known by about 10 percent of visually impaired in the United States, and is almost unknown among the sighted. A sighted user, confronted in an emergency situation by a telephone key pad in which every key bears a different “tactile indicator”, all of which are incomprehensible to the user, is likely to be more delayed that if the key pad bore no tactile indicators whatsoever.
U.S. Pat. No. 5,444,775 describes a telephone with a key pad which has been modified by mounting “locator aids” on the telephone itself, these locator aids each being in the form of a hinged plastic strip having an aperture arranged to lie adjacent a selected key; two such locator aids enable the 1 and 9 keys to be identified by touch. The locator aids appear likely to be a substantial nuisance during normal use of the telephone and are susceptible to mechanical damage, especially when employed on cellular or cordless telephones.
It is of course well known to provide telephone key pads with keys in addition to the normal 0, 1-9, * and # keys; for example, many telephones are equipped with speed-dialing keys for dialing pre-programmed numbers (see, for example U.S. Pat. No. 6,212,271), and many office telephones are provided with “Hold” and “Transfer” keys. It has been suggested that a “911” key be provided on a telephone so that this emergency number could be dialed with a single key press; see, for example, U.S. Pat. Nos. 4,866,764 and 5,365,570. However, there is no agreement as to the size and placement of the 911 key relative to the other keys of a regular key pad, so that a guest in a residence or hotel would not know how to find the 911 key by touch, and indeed a homeowner who has several telephones from various manufacturers scattered around his or her house might have difficulty in an emergency remembering where the 911 key is on any particular telephone.
Furthermore, telephones provided with single key press 911 dialing tend to generate a disproportionate number of false alarms. Young children may play with a telephone, or an adult might inadvertently touch the 911 key while reaching for one of the other keys. Although it might be thought that such false alarms could readily be disposed of by the emergency operator talking to the telephone user, a child might not be able to explain the situation, and in any case laws or regulations in many communities require that once a 911 call has been made, police must be dispatched to check the location from which the call is made, in order to ensure that, for example, a person making a 911 call and then denying a need for assistance is not the victim of a hostage situation, domestic violence or a similar situation involving coercion.
It has also been suggested telephones be able to dial 911 by voice activation. However, voice activated systems are notoriously unreliable, especially when they are required to cope with numerous different users, background noise etc., and such difficulties are exacerbated in emergency situations, where people are unlikely to be speaking in the calm, clear voice for which most voice activated systems are designed. Furthermore, in some emergency situations, as for example when a homeowner suspects that a burglar is inside his house and wishes to summon police, voice activation is especially inappropriate.
For the foregoing reasons, none of the prior art proposals for facilitating dialing of 911 in emergencies is satisfactory, and a solution is required which meets as many as possible of the following criteria:                (a) the solution should enable a user to distinguish the 1 and 9 keys by touch from the other keys on the key pad, and from each other;        (b) the solution should not clutter the other number keys on the key pad with tactile indicators which are likely to confuse a user;        (c) the solution should allow for tactile recognition of all keys (for example, the “on” and “send” keys on a cellular telephone) which may be required to dial a 911 call;        (d) the solution should not hinder normal use of the telephone;        (e) the solution should be readily applicable to telephones varying size and shape;        (f) the solution should if possible permit retrofitting of existing telephones; and        (g) the solution should be inexpensive.        
It is a primary object of the present invention to provide a solution which can meet all of the foregoing criteria.
It is another object of the present invention to provide a method by which an existing telephone can be modified in a simple and inexpensive manner to enable the 1 and 9 keys, and optionally any other keys required to make an emergency call, to be distinguished by touch.
Other objects of the invention and will in part appear hereinafter and will in part be obvious when the following detailed description is read in connection with the drawings.